9:25 PM EDT November 2. 2012 - NEW YORK — The New York City Marathon will not be run Sunday, Mayor Michael Bloomberg's office announced late Friday afternoon. It's the first cancellation in the race's 42-year history.

Earlier, Bloomberg defended his decision to go ahead with the 26.2-mile run, saying it would give the storm-ravaged city "something to cheer about." Critics argued that the race would take resources away from recovery efforts and that it was insensitive to New Yorkers hit hard by Hurricane Sandy.

"While holding the race would not require diverting resources from the recovery effort, it is clear that it has become the source of controversy and division," Bloomberg and Mary Wittenberg, the president of the New York Runners,  said in a joint statement.

"The marathon has always brought our city together and inspired us with stories of courage and determination. We would not want a cloud to hang over the race or its participants, and so we have decided to cancel it. We cannot allow a controversy over an athletic event – even one as meaningful as this – to distract attention away from all the critically important work that is being done to recover from the storm and get our city back on track."

The statement concluded by saying the Road Runners would have additional information "in the days ahead for participants."

More than 47,000 people signed up for this year's race, although organizers had estimated that about 8,000 of 30,000 out-of-towers would not show.

At a hastily called evening news conference, an emotional Wittenberg said she and other marathon officials had felt that dedicating the race to New York City's recovery would help hurricane victims.

But, amid mounting criticism of the decision to hold the race while emergency storm efforts continue, she said it was "with incredibly heavy hearts" that organizers concluded the best way to help the city was to cancel the race.

At the briefing, Deputy Mayor Howard Wolfson said the race had become "divisive and controversial" and "a distraction" to storm-relief efforts.

Canceling it, he said, was "a difficult decision, it was a painful decision," but it was the right decision.

"If it's not unifying, it is not the marathon," he said, describing the race as "one of the very best days in the life of the city .. a moment of unity and happiness and joy and a celebration."

Addressing those struggling to cope with the hurricane's destruction, Wolfson said, "We will bring comfort and relief to people who are suffering. We will rebuild our city, we will rebuild it better than it ever was."

Critics — including lawmakers — had slammed Bloomberg's earlier decision to hold the marathon as "idiotic," insensitive and a diversion of city resources at a time when New Yorkers have lost power, their homes and their loved ones.

Thousands of runners joined online appeals to boycott the event or volunteer instead on Sunday to help stricken families.

The city resources required by the marathon, he said, were not resources that would make a difference in storm recovery efforts. "If I thought it would take resources away" from emergency work, "we would not do that," he said.

The mayor noted that Rudy Giuliani, his predecessor who had staged the annual race only weeks after the 9/11 attacks, supported his decision as a way to demonstrate solidarity among New Yorkers.